Pat O. Daily

Temporal response of left ventricular performance to mitral valve surgery.

We separated MR patients into two subgroups. In 12 subjects (group 1) with preoperative EDD = 5.94 0.42 cm, ESD = 3.55 ± 0.43 cm, and EF = 0.70 ± 0.05, EF fell slightly by 6 months after surgery to 0.59 ± 0.10 (p < 0.01), but remained within the normal range. Concomitantly, left ventricular hypertrophy regressed, as CSA was 24.2 6.5 cm2 before and 18.6 ± 2.4 cm2 after surgery (p < 0.01). contrast, in four subjects (group 2) with preoperative EDD = 8.07 ± 0.35 cm, ESD = 5.69 ± 0.70 cm, and EF = 0.57 ± 0.05, left ventricular function progressively deteriorated after surgery, with EF falling 0.26 ± 0.06 (p < 0.01). In the latter group left ventricular hypertrophy did not regress (CSA = 31.5 ± 4.5 cm2 before and 31.9 ± 3.4 cm2 after surgery, NS). Techniques for myocardial preservation during mitral valve surgery did not differ between the MR and MS groups. In group 2 MR subjects, there was no evidence of intraoperative myocardial infarction.

Aprotinin for Primary Coronary Artery Bypass Grafting: A Multicenter Trial of Three Dose Regimens

BACKGROUND High-dose aprotinin reduces transfusion requirements in patients undergoing coronary artery bypass grafting, but the safety and effectiveness of smaller doses is unclear. Furthermore, patient selection criteria for optimal use of the drug are not well defined. METHODS Seven hundred and four first-time coronary artery bypass grafting patients were randomized to receive one of three doses of aprotinin (high, low, and pump-prime-only) or placebo. The patients were stratified as to risk of excessive bleeding. RESULTS All three aprotinin doses were highly effective in reducing bleeding and transfusion requirements. Consistent efficacy was not, however, demonstrated in the subgroup of patients at low risk for bleeding. There were no differences in mortality or the incidences of renal failure, strokes, or definite myocardial infarctions between the groups, although the pump-prime-only dose was associated with a small increase in definite, probable, or possible myocardial infarctions (p = 0.045). CONCLUSIONS Low-dose and pump-prime-only aprotinin regimens provide reductions in bleeding and transfusion requirements that are similar to those of high-dose regimens. Although safe, aprotinin is not routinely indicated for the first-time coronary artery bypass grafting patient who is at low risk for postoperative bleeding. The pump-prime-only dose is not currently recommended because of a possible association with more frequent myocardial infarctions.

A 27-year experience with surgical treatment of Budd-Chiari syndrome.

ObjectiveTo determine the effects of surgical portal decompression in Budd-Chiari syndrome (BCS) on survival, quality of life, shunt patency, liver function, portal hemodynamics, and hepatic morphology during periods ranging from 3.5 to 27 years. Summary Background DataExperiments in the authors’ laboratory showed that surgical portal decompression reversed the deleterious effects of BCS on the liver. This study was aimed at determining whether similar benefit could be obtained in patients with BCS. MethodsFrom 1972 to 1999, the authors conducted prospective studies of the treatment of 60 patients with BCS who were divided into three groups: the first had occlusion confined to the hepatic veins treated by direct side-to-side portacaval shunt (SSPCS); the second had occlusion involving the inferior vena cava (IVC) treated by a portal decompressive procedure that bypassed the obstructed IVC; and the third group, who had advanced cirrhosis and hepatic decompensation and were referred too late for treatment by portal decompression, required orthotopic liver transplantation. ResultsIn the 32 patients with BCS resulting from hepatic vein occlusion alone, SSPCS had a surgical death rate of 3%, and 94% of the patients were alive 3.5 to 27 years after surgery. All 31 survivors remained free of ascites and almost all had normal liver function. No patient with a patent shunt had encephalopathy. The SSPCS remained patent in all but one patient. Liver biopsies showed no evidence of congestion or necrosis, and 48% of the biopsies were diagnosed as normal. Mesoatrial shunt was performed in eight patients with BCS caused by IVC thrombosis. All patients survived surgery, but five subsequently developed thrombosis of the synthetic graft and died. Because of the poor results, mesoatrial shunt was abandoned. Instead, a high-flow combination shunt was introduced, consisting of SSPCS combined with a cavoatrial shunt (CAS) through a Gore-Tex graft. There were no surgical or long-term deaths among 10 patients who underwent combined SSPCS and CAS, and the shunts functioned effectively during 4 to 16 years of follow-up. Ten patients with advanced cirrhosis were referred too late to benefit from surgical portal decompression, and they were approved and listed for orthotopic liver transplantation. Three patients died of liver failure while awaiting a transplant, and four patients died after the transplant. The 1- and 5-year survival rates were 40% and 30%, respectively. ConclusionsSSPCS in BCS with hepatic vein occlusion alone results in reversal of liver damage, correction of hemodynamic disturbances, prolonged survival, and good quality of life when performed early in the course of BCS. Similarly good results are obtained with combined SSPCS and CAS in patients with BCS resulting from IVC occlusion. In contrast, mesoatrial shunt has been discontinued in the authors’ program because of an unacceptable incidence of graft thrombosis and death. In patients with advanced cirrhosis from long-standing, untreated BCS, orthotopic liver transplantation is the only hope of relief and results in the salvage of some patients. The key to long survival in BCS is prompt diagnosis and treatment by portal decompression.

Thromboendarterectomy for Chronic, Major-Vessel Thromboembolic Pulmonary Hypertension: Immediate and Long-Term Results in 42 Patients

Since 1970, forty-two patients with pulmonary hypertension due to chronic, thromboembolic obstruction of the major pulmonary arteries have had pulmonary thromboendarterectomy at the University of California, San Diego, and the San Diego Veterans Medical Centers. Duration of symptoms before admission averaged 4.4 years, with many alternative diagnoses having been made. At admission, 29 patients had class IV disease by New York Heart Association criteria, and 12, class III. Immediately after surgery, pulmonary vascular resistance declined significantly (p less than 0.001) from 897 +/- 352 dynes/s.cm-5 to 278 +/- 135 dynes/s.cm-5. Seven patients with class IV disease died in the postoperative period. Of the 35 survivors (mean follow-up, 28 months), 16 had class I disease; 18, class II; and 1, class III. Of the 17 patients who have returned for cardiac catheterization at 4 to 12 months after surgery, a further decline (p less than 0.05) in pulmonary vascular resistance has occurred. This experience indicates that the disorder is commoner than we previously suspected and that thromboendarterectomy is feasible, even in patients with severe and protracted hemodynamic compromise.

Improved patient survival after cardiac arrest using a cardiopulmonary support system

A portable cardiopulmonary bypass system that can be rapidly deployed in a nonsurgical setting using nursing staff was used in 38 patients with cardiovascular collapse refractory to ACLS protocol. Percutaneous or cutdown cannulation sites were: femoral vein-femoral artery (n = 18), right internal jugular vein-femoral artery (n = 2), right atrium-ascending aorta (n = 12), or a combination approach (n = 4). Two patients could not be cannulated. Patient diagnoses were pulmonary emboli (n = 3), failed coronary angioplasty (n = 7), myocardial infarction with cardiogenic shock (n = 5), trauma (n = 7), aortic stenosis (n = 2), postcardiotomy deterioration (n = 10), deterioration after cardiac transplantation (n = 2), cardiomyopathy with shock (n = 1), and ruptured ascending aortic dissection (n = 1). Ninety-five percent of patients (36 of 38) were successfully resuscitated to a stable rhythm. Eight diagnostic procedures (coronary angiography, n = 4; pulmonary angiography, n = 3; and aortography, n = 1) were performed while patients were on cardiopulmonary support. Early deaths resulted from massive hemorrhage (n = 8), inability to cannulate (n = 2), and irreversible myocardial injury (n = 10). Sixty-six percent (24 of 36) of patients successfully cannulated underwent conversion to standard cardiopulmonary bypass with attendant operative procedure or placement of ventricular assist device or total artificial heart. Fifty percent (18 of 36) of patients cannulated were successfully weaned from cardiopulmonary support, and 17% (6/36) are long-term survivors.(ABSTRACT TRUNCATED AT 250 WORDS)

Serial noninvasive assessment of left ventricular hypertrophy and function after surgical correction of aortic regurgitation

Serial echocardiographic analyses of left ventricular hypertrophy and function, with validation of extent of shortening by first pass radionuclide angiography, was performed in 16 patients before and after surgical correction of severe aortic valve regurgitation. All patients were symptomatic (predominantly in New York Heart Association functional class III or IV) before operation but were in class I or II after operation. The preoperative pattern of eccentric hypertrophy (increased mass with normal ratio of left ventricular cross-sectional wall area to cavity area) changed immediately after operation to a pattern of concentric hypertrophy (increased mass with increased ratio of left ventricular cross-sectional wall area to cavity area) because of a significant reduction in chamber size and increase in wall thickness. On late follow-up (9 to 35 months, average 15 months after operation), the hypertrophy lessened significantly, the cross-sectional area of the ventricular wall decreasing to 21.1 ± 5.4 (mean ± standard deviation) cm2 from a preoperative average of 31.6 ± 4.8 cm2 (P < 0.01), and the ratio of wall area to cavity area was once again normal. In the same period, left ventricular enddiastolic diameter decreased from 6.52 ± 0.68 to 4.64 ± 0.52 cm (P < 0.01). Preoperatively, ejection phase indexes were normal or only marginally depressed in 12 of 16 patients but were moderately depressed in the remaining 4. At early follow-up (average 4 months) ventricular shortening tended to increase; and at late follow-up the fractional shortening of the minor axis, the ejection fraction and the mean velocity of circumferential fiber shortening increased to 0.39 ± 0.07, 0.68 ± 0.10 and 1.26 ± 0.22 circumference/sec, respectively, from preoperative values of 0.33 ± 0.09, 0.60 ± 0.14 and 1.05 ± 0.31 circumferences/sec (P < 0.05 for each index). In the four subjects with preoperative depression of left ventricular function, the extent and speed of myocardial shortening at late follow-up became normal in three subjects and remained moderately depressed in one patient. Paradoxical septal motion was observed immediately postoperatively and in the early follow-up studies, but it was noted in only 3 of 16 cases by the late follow-up period. Provided septal dyskinesia was not present, echocardiographic and first pass radionuclide determinations of ejection fraction correlated highly (r = 0.92). It is concluded that when aortic valve replacement for symptomatic aortic regurgitation is undertaken prior to severe myocardial decompensation, improvement in clinical status is associated with significant regression of myocardial hypertrophy, reduction in left ventricular size, evolution of a normal massvolume ratio, recovery of septal dyskinesia as revealed on echocardiography, and improvement in left ventricular function. These data do not define the type and degree of left ventricular dysfunction which is irreversible.

Interventricular septal motion and left ventricular function after coronary bypass surgery: evaluation with echocardiography and radionuclide angiography.

To evaluate interventricular septal motion and left ventricular function after coronary bypass graft surgery, 40 patients were studied early postoperatively and serially for up to 16 months with echocardiography and radionuclide angiography. Early after operation mean left septal excursion decreased significantly from 4.6 +/- 0.4 (standard error) to 0.8 +/- 0.6 mm (P less than 0.001), and left septal motion was abnormal in 23 of the 40 patients. Mean right septal excursion reversed from 2.1 +/- 0.5 to -2.1 +/- 0.5 mm early after operation in the 22 patients in whom these measurements could be made, and 15 patients showed paradoxical right septal excursion. At a mean of 4 months after operation, only 7 of 35 patients followed up had abnormal left septal motion, and mean left septal excursion had returned toward normal (3.6 +/- 0.7 mm); mean right septal excursion remained reversed (--1.1 +/- 0.7 mm), and 6 of the 14 patients followed up had paradoxical motion. In the 22 patients whose wall thickness could be measured, mean septal thickening during systole decreased significantly from 35 +/- 4 to 21 +/- 3 percent early after operation (P less than 0.01). During late follow-up septal thickening returned toward normal (32 +/- 4 percent). Mean normalized posterior wall velocity increased significantly after operation from 0.76 +/- 0.03 to 1.01 +/- 0.05 sec-1 (P less than 0.001), but posterior wall thickening remained unchanged. Left ventricular end-diastolic dimension and the radionuclide-determined left ventricular ejection fraction were unchanged postoperatively. It is concluded that (1) echocardiographically detected abnormal septal movement is frequent early after coronary bypass graft operation; (2) both decreased myocardial contraction in the septum and increased anterior movement of the whole heart contribute to this abnormality; (3) the abnormalities in septal movement decrease during late follow-up in many patients but persist in some patients; and (4) posterior wall function tends to increase early after operation and therefore overall left ventricular function remains normal.

Apparent coagulopathy caused by infusion of shed mediastinal blood and its prevention by washing of the infusate

We found that reinfusion of shed mediastinal blood (SMB) after a cardiac operation was associated with laboratory evidence of disseminated intravascular coagulation. In view of this, we compared the effect of infusing washed or unwashed SMB on the coagulation profiles and blood use of two serial groups of patients undergoing cardiopulmonary bypass. We found that the results of testing for fibrin degradation products converted from negative to positive in 17 of 20 patients who received unwashed SMB versus 1 of 14 patients who received washed SMB (p less than 0.0001). Other coagulation studies did not reveal disseminated intravascular coagulation in either group, nor were there differences in blood use between the two groups. The unwashed SMB contained high titers of fibrin degradation products (mean reciprocal titer = 354 +/- 161) compared with washed SMB (mean reciprocal titer = 34 +/- 18) (p less than 0.01). Based on the volume of SMB infused, the amount of fibrin degradation products in unwashed SMB was sufficient to account for the positive fibrin degradation product assays after infusion in this group. We conclude that infusion of unwashed SMB may confuse the interpretation of tests for disseminated intravascular coagulation or fibrinolysis. As this could lead to unnecessary blood component use and is preventable by washing before infusion, we recommend that the routine infusion of unwashed SMB no longer be employed.

Epicardial activation and repolarization patterns in patients with right ventricular hypertrophy.

To map globalepicardialrepolarizationpatternsandtestthe “SI” modelofTwave generation, the patterns of epicardial activation and repolarization in patients with chronic pulmonary thromboembolism and right ventricular hypertrophy were studied by computerized mapping techniques and monophasic action potential (MAP) recordings. The ventricular activation patterns were characterizedbydelayed rightventricularactivation and the absenceofnormal early epicardial ventricular breakthrough in some cases. The repolarization patterns were characterized bynonuniform distribution ofTwave morphologies. The Twaves were predominantly positive over the left ventricular epicardium and negative or biphasic over the right ventricularepicardium. Theactivation-recovery (A-R) intervalswere measured from thelocal activation tothemaximal dV/dtoftheupstroke ofthe Twaves (Wyattmethod).Thedifference betweentheA-RintervalsandtheMAPfromonsetofactivationto90%repolarization (MAP90) varies accordingtoTwave morphologyandcould be as highas 96 msec with positiveTwaves, despite significant correlations (r = 0.56–0.90) between MAP90 and A-R intervals for each morphology. BetteroverallcorrelationswerefoundiftheminimaldV/dton thedownslopeofthe positive Twaves was chosen to estimate the time oflocal repolarization (alternative method). Using this method, the mean A-R intervals were the same over the right and left ventricles. Cardiopulmonary bypass significantly prolonged the action potential duration equally at all parts ofthe epicardium. We conclude that in patients with rightventricular hypertrophy, the timeoflocalrepolarization can bestbeestimatedbyour alternativemethod;therightventricle completes activation and repolarization laterthan the leftventricle, and the distribution ofT wave morphologies is nonuniform, with predominantly positive Twaves observed over the left ventricleandnegativeor biphasicTwaves observedover therightventricle. Thesefindings are compatiblewith the SI model ofthe generation ofTwaves.

Cost reduction by combined carotid endarterectomy and coronary artery bypass grafting

A significant cost reduction is likely if patients who require coronary artery bypass grafting with significant carotid stenosis have simultaneous carotid endarterectomy and bypass grafting, provided risk is not increased. To investigate this issue, we retrospectively identified cases from February 1977 to May 1994 with first-time isolated carotid endarterectomy, coronary bypass, or combined procedures. In the isolated carotid endarterectomy population, median age was 69 years and 58% (85/146) were male, as compared with 68 years and 68% (68/100) male in the combined group; median age of the coronary bypass cohort was 65 years and 76% (381/500) male. A significantly higher percentage of patients in the coronary bypass versus combined group were in New York Heart Association functional class IV. In the combined group there was a significantly higher incidence of older age, diabetes, hypertension, hyperlipidemia, renal failure, and congestive heart failure. There was no difference among the three groups with respect to hospital mortality (0%, 3.4%, and 4.0%, respectively) and permanent stroke (0.7%, 1.2%, and 0%, respectively). Hospital costs were